Filtering the students

On the Blog Dangerously Irrelevant, Scott McLeod writes about web filtering in schools. There has been much discussion on this topic for many years. Hearing Nancy Willard of the Center for Safe and Responsible Internet Use, speak about the topic at NECC '07 helped me form my opinions. How much filtering do we need in schools? I think minimal, and even that it is often times too much. Wes Fryer asked last February about differentiated filtering. Which is a good idea, I guess.
I really don't like any filtering. No different from any other book banning of editing out pages of an encyclopedia. The big problem is classroom management and having firm assignments for the students when they are on-line. The teacher needs to be aware of what is going on in the class and have an idea of appropriateness.
The Internet is a tool, and with any tool we need to show how to use it. I still monitor my teenagers when they are using my power tools, and monitor where they are on-line.
As with any other inappropriate classroom behavior, Internet use must be monitored.
I hear from other teachers on how tools such as skype, plurk and twitter are blocked by their school networks. Why? Bandwidth argument I can see with skype, but otherwise why? In schools we must pay attention to the fact that the network is there for education and access. So don't block useful tools.